When can PE be excluded without CTPA?

PE unlikely (Wells ≤4) + negative high-sensitivity D-dimer excludes PE without CTPA (negative LR ~0.1). The PERC rule can exclude PE in very low-risk patients without D-dimer if all 8 criteria are negative.

What is the YEARS algorithm for PE diagnosis?

YEARS uses 3 criteria (clinical signs of DVT, haemoptysis, PE as most likely diagnosis) combined with D-dimer thresholds (<500 ng/mL if no criteria, <1000 ng/mL if ≥1 criterion) to safely exclude PE and reduce CTPA utilization by ~14%.

Pulmonary Embolism Wells Score Pre-test Probability

Estimates PE pre-test probability: ≤4 points = PE unlikely (12.1% prevalence); >4 = PE likely (37%). Points: clinical signs of DVT (3), no alternative diagnosis (3), heart rate >100 (1.5), immobilization/surgery in past 4 weeks (1.5), prior DVT/PE (1.5), haemoptysis (1), malignancy (1).

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Pulmonary Embolism Wells Score Pre-test Probability

Frequently Asked Questions

When can PE be excluded without CTPA?

What is the YEARS algorithm for PE diagnosis?